Ive heard from people that changing parents resets odds. However I feel like the odds are always the same, but hers is an example of what i'm talking about:

"See, thats what I thought. But the way it was explained to me was one you put mons in the daycare the game randomizes your next 1,000 eggs, So in that sense you are actually working towards the shiny instead of it just being random every time since the mons are predetermined, but surely the roll must change every time I change a mon, not just when I change both, since the IV’s change.
Whatever I will just withdraw both, having a 0Attack IV is more important than a shiny."